8<--- cut here --- Unable to handle kernel paging request at virtual address fee04f2a when write [fee04f2a] *pgd=80000080007003, *pmd=00000000 Internal error: Oops: a06 [#1] SMP ARM Modules linked in: CPU: 0 UID: 0 PID: 8769 Comm: syz.4.1139 Tainted: G L syzkaller #0 PREEMPT Tainted: [L]=SOFTLOCKUP Hardware name: ARM-Versatile Express PC is at __raw_writeb arch/arm/include/asm/io.h:88 [inline] PC is at subdev_8255_io drivers/comedi/drivers/comedi_8255.c:47 [inline] PC is at subdev_8255_io+0x60/0x6c drivers/comedi/drivers/comedi_8255.c:43 LR is at subdev_8255_io drivers/comedi/drivers/comedi_8255.c:47 [inline] LR is at subdev_8255_io+0x4c/0x6c drivers/comedi/drivers/comedi_8255.c:43 pc : [<814388e0>] lr : [<814388cc>] psr: 60000013 sp : df955cb8 ip : df955cb8 fp : df955cd4 r10: 00000000 r9 : 00000084 r8 : df955da4 r7 : 00004f27 r6 : 0000009b r5 : 846d8180 r4 : 00004f2a r3 : 0000009b r2 : fee04f2a r1 : 00000001 r0 : 846d8180 Flags: nZCv IRQs on FIQs on Mode SVC_32 ISA ARM Segment user Control: 30c5387d Table: 860b7f80 DAC: fffffffd Register r0 information: slab kmalloc-192 start 846d8180 pointer offset 0 size 192 Register r1 information: non-paged memory Register r2 information: 0-page vmalloc region starting at 0xfee00000 allocated at pci_reserve_io+0x0/0x38 arch/arm/mm/mmu.c:1055 Register r3 information: non-paged memory Register r4 information: non-paged memory Register r5 information: slab kmalloc-192 start 846d8180 pointer offset 0 size 192 Register r6 information: non-paged memory Register r7 information: non-paged memory Register r8 information: 2-page vmalloc region starting at 0xdf954000 allocated at kernel_clone+0xac/0x428 kernel/fork.c:2654 Register r9 information: non-paged memory Register r10 information: NULL pointer Register r11 information: 2-page vmalloc region starting at 0xdf954000 allocated at kernel_clone+0xac/0x428 kernel/fork.c:2654 Register r12 information: 2-page vmalloc region starting at 0xdf954000 allocated at kernel_clone+0xac/0x428 kernel/fork.c:2654 Process syz.4.1139 (pid: 8769, stack limit = 0xdf954000) Stack: (0xdf955cb8 to 0xdf956000) 5ca0: 81438880 00004f27 5cc0: 846d8180 00004f27 df955cf4 df955cd8 814385bc 8143888c 00004f27 80522490 5ce0: 83e3e000 83e3e000 df955d14 df955cf8 81438974 81438570 846d8180 00000000 5d00: 83e3e000 00004f27 df955d54 df955d18 81438b24 814388f8 82b0c514 8334c300 5d20: 82821780 00000000 00000000 829d6d44 846d8180 00000000 df955d90 846d8180 5d40: 00000000 82b2efdc df955d8c df955d58 81427510 81438abc 40946400 00000000 5d60: df955d7c 200000c0 846d8180 b5403587 40946400 8582ec00 00000003 846d81b0 5d80: df955e4c df955d90 81422e48 81427410 35353238 00000000 00000000 00000000 5da0: 00000000 00004f27 00000005 00000002 00000401 00000001 00000cc7 00000fff 5dc0: 5c952399 00000005 000003ff 00000802 00001600 00000001 00000001 00000009 5de0: 0000e1cb 00000006 00000004 00000003 00000395 80000089 fffffffd 00000000 5e00: fffffff5 ffffeadb 00000003 0000003c 00000008 00000004 08000000 dffffffa 5e20: 00000000 9e3f9189 00000000 85fe7240 846d8180 200000c0 40946400 8582ec00 5e40: df955f14 df955e50 814239c8 81422d80 00000000 9e3f9189 00000000 00000000 5e60: 824b557c df955ea4 0000005f 845ce640 00000064 84135d44 df955ee4 df955e88 5e80: 807cd6ec 807c3ac4 00000064 00000001 00000000 df955ea4 8389ba90 834d6440 5ea0: 00006400 0000000b df955e98 00000000 00000000 9e3f9189 00000000 85fe7240 5ec0: 40946400 200000c0 200000c0 85fe7240 00000008 8582ec00 df955ef4 df955ee8 5ee0: 807cd81c 9e3f9189 df955f14 00000000 85fe7241 40946400 200000c0 85fe7240 5f00: 00000008 8582ec00 df955fa4 df955f18 8058f600 814238d0 ecac8b10 8582ec00 5f20: df955f3c df955f30 81adb9f4 81adb8c0 df955f54 df955f40 8025a85c 8028c030 5f40: df955fb0 40000000 df955f84 df955f58 80220bf8 8025a818 00000000 8281d27c 5f60: df955fb0 0013ddc0 ecac8b10 80220b4c 00000000 9e3f9189 df955fac 00000000 5f80: 00000000 003463b0 00000036 8020029c 8582ec00 00000036 00000000 df955fa8 5fa0: 80200060 8058f3c8 00000000 00000000 00000008 40946400 200000c0 00000000 5fc0: 00000000 00000000 003463b0 00000036 00346378 00000000 00000001 76f6c0dc 5fe0: 76f6be88 76f6be78 00018734 0012fc20 60000010 00000008 00000000 00000000 Call trace: [<81438880>] (subdev_8255_io) from [<814385bc>] (subdev_8255_do_config+0x58/0x60 drivers/comedi/drivers/comedi_8255.c:115) r7:00004f27 r6:846d8180 r5:00004f27 r4:81438880 [<81438564>] (subdev_8255_do_config) from [<81438974>] (__subdev_8255_init drivers/comedi/drivers/comedi_8255.c:172 [inline]) [<81438564>] (subdev_8255_do_config) from [<81438974>] (subdev_8255_io_init+0x88/0x98 drivers/comedi/drivers/comedi_8255.c:192) r4:83e3e000 [<814388ec>] (subdev_8255_io_init) from [<81438b24>] (dev_8255_attach drivers/comedi/drivers/8255.c:82 [inline]) [<814388ec>] (subdev_8255_io_init) from [<81438b24>] (dev_8255_attach+0x74/0x120 drivers/comedi/drivers/8255.c:46) r7:00004f27 r6:83e3e000 r5:00000000 r4:846d8180 [<81438ab0>] (dev_8255_attach) from [<81427510>] (comedi_device_attach+0x10c/0x248 drivers/comedi/drivers.c:1069) r10:82b2efdc r9:00000000 r8:846d8180 r7:df955d90 r6:00000000 r5:846d8180 r4:829d6d44 [<81427404>] (comedi_device_attach) from [<81422e48>] (do_devconfig_ioctl+0xd4/0x21c drivers/comedi/comedi_fops.c:928) r10:846d81b0 r9:00000003 r8:8582ec00 r7:40946400 r6:b5403587 r5:846d8180 r4:200000c0 [<81422d74>] (do_devconfig_ioctl) from [<814239c8>] (comedi_unlocked_ioctl+0x104/0x1c80 drivers/comedi/comedi_fops.c:2240) r8:8582ec00 r7:40946400 r6:200000c0 r5:846d8180 r4:85fe7240 [<814238c4>] (comedi_unlocked_ioctl) from [<8058f600>] (vfs_ioctl fs/ioctl.c:51 [inline]) [<814238c4>] (comedi_unlocked_ioctl) from [<8058f600>] (do_vfs_ioctl fs/ioctl.c:551 [inline]) [<814238c4>] (comedi_unlocked_ioctl) from [<8058f600>] (__do_sys_ioctl fs/ioctl.c:595 [inline]) [<814238c4>] (comedi_unlocked_ioctl) from [<8058f600>] (sys_ioctl+0x244/0xb5c fs/ioctl.c:583) r10:8582ec00 r9:00000008 r8:85fe7240 r7:200000c0 r6:40946400 r5:85fe7241 r4:00000000 [<8058f3bc>] (sys_ioctl) from [<80200060>] (ret_fast_syscall+0x0/0x1c arch/arm/mm/proc-v7.S:67) Exception stack(0xdf955fa8 to 0xdf955ff0) 5fa0: 00000000 00000000 00000008 40946400 200000c0 00000000 5fc0: 00000000 00000000 003463b0 00000036 00346378 00000000 00000001 76f6c0dc 5fe0: 76f6be88 76f6be78 00018734 0012fc20 r10:00000036 r9:8582ec00 r8:8020029c r7:00000036 r6:003463b0 r5:00000000 r4:00000000 Code: e6ef3076 e0842002 e7f32052 e2422612 (e5c23000) ---[ end trace 0000000000000000 ]--- ---------------- Code disassembly (best guess): 0: e6ef3076 uxtb r3, r6 4: e0842002 add r2, r4, r2 8: e7f32052 ubfx r2, r2, #0, #20 c: e2422612 sub r2, r2, #18874368 @ 0x1200000 * 10: e5c23000 strb r3, [r2] <-- trapping instruction